JPS6044837A - Waveform regenerating device - Google Patents

Abstract

PURPOSE:To regenerate a signal having large amplitude with high resolution, by using all data bits in a waveform regenerating device as level bits. CONSTITUTION:When a player operates the key of a sound, a signal corresponding to the key is read out of a memory 16 in response to the digital output of a counter 6. The read signal is supplied to a variable gain amplifier 15 after DA conversion by a DA converter 7. The signal from the memory 16 is also supplied to an AND circuit (gain-changing-code detecting circuit) 19, where the signal is always compared with gain changing codes. When the signal read from the memory 16 is a part having large amplitude, the output (g) of the AND circuit 19 is at an L level. Therefore the output of an inverter 20 becomes an H level, and a switch 21a is turned ON. Meanwhile, since the output (h) of a flip-flop 22 is at an L level, the gain of the variable gain amplifier 15 is 1. Thus the signal at the part having the large amplitude is supplied to a low-pass filter 8 at its own level. A signal (i), from which unnecessary frequency components are removed is outputted from a terminal 9.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a waveform reproducing device, which uses all data bits as level bits, and can reproduce particularly large amplitude signals with high resolution compared to conventional devices that provide gain bits for the data bits. The purpose is to provide a playback device.

Conventionally, there are electronic organs that produce sound by shaping the output signal from an oscillation circuit to approximate the waveform of the sound from each musical instrument, but in recent years, the sound from the actual musical instrument has been written as a digital signal. Digital electronic organs have been developed that read out predetermined tones from stored memory and produce them.

In the latter case, the manufacturer has built-in a memory in which the sounds from an actual musical instrument such as a piano have been recorded in advance and written in digital signals, and the user can select a predetermined number from this memory when performing. Reads the signal, converts it to analog, and produces sound. This device is useful because it can produce sounds that are much closer to the timbre of an actual musical instrument than conventional electronic organs.

FIGS. 1A and 1B show block diagrams of an example of a conventional waveform recording device and a conventional waveform reproducing device applied to a digital electronic organ, respectively. In the same figure (A), a signal from an actual musical instrument that enters terminal 1 is filtered by a low-pass filter 2 to remove components above the recordable frequency band, and then sampled at predetermined intervals by a sample-and-hold circuit 3. AD after being
The data is AD converted by the converter 4 and written into the memory 5. In this case, sample and hold circuit 3. The AD converter 4 and the memory 5 operate in synchronization with the same II pulse from the counter 6.

In the same figure (B), the signal from the memory 5 which is successively outputted by the synchronization pulse from the counter 6 is converted to DA by the DA converter 7.
The signal is converted, unnecessary frequency components are removed by a low-pass filter 8, and then outputted from a terminal 9.

If the number of bits of the digital signal is N, then
For a full-scale input signal shown in Figure 2 (A), there is a resolution of 2, while for a 1/2M full-scale input signal shown in Figure 2 (B), there is a resolution of 2 (A/-). M),
, becomes the resolution. In this way, this conventional device has a small number of quantizations, especially for input signals with small amplitudes, so it cannot record waveforms faithfully, generates distortion and hanging noise, and has low S/N.
The disadvantage was that the ratio was low.

FIGS. 3A and 3B show block diagrams of other examples of a conventional waveform recording device and a conventional waveform reproducing device applied to a digital electronic organ, respectively. During recording, the signal taken out from the sample-and-hold circuit 3 is supplied to the attenuator 10 and the comparator 11 in FIG. Ru. Here, if the input signal is below the reference value 1.22 as shown in FIG. 4(A), an L level signal is sent as shown in FIG. The H level signal is taken out and supplied to attenuator 1o and memory 12.

The signal C supplied from the comparator 11 to the memory 12 is a gain bit of one bit out of all data bits (for example, eight bits).

For example, as shown in FIG. 5, the attenuator 10 has a gain of (R'+ +R2)/R2 and a high input impedance.
It is composed of an amplifier 10a, a resistor RI+L2, and the like. When the signal from the comparator 11 supplied to the terminal 1ob is at L level, the pirated analog switch 10c
is turned on, and the signal from the sample-and-hold circuit 3 that enters the terminal 100 is sent to the amplifier 10a T" (R1+R
2) While it is multiplied by /R2 and taken out from terminal 10f,
When the signal from the comparator 11 supplied to the terminal 10b is at H level, the parallel analog switch 10d is turned on, and the signal input to the terminal 10e is passed through the resistor R+,
After R2 is multiplied by R2/(R1+R2), the amplifier 10a
Then, it is multiplied by (R+-IR2)/R2 (eventually it is reduced to 1) and taken out from the terminal 10.

The signal taken out from the attenuator 10 is AD converted by the AD converter 4 and converted into all data bits (e.g. 8 bits).
It is set as the middle 7 level bits and written into the memory 12. In this case, if the input signal a is less than the reference value fl+, Q2, it is multiplied by (R1+R2)/2 and its gain bit is set to "0" and written to the memory 12, while the input signal a is If the value Il+ is 112 or more, the level remains unchanged and the gain bit is
1'' and written into the memory 12.

During playback, in FIG. 3(B), the level data read from the memory 12 is DA-converted by the DA converter 7 and supplied to the attenuator 13, while the gain data read from the memory 12 is supplied to the inverter 14. The signal is level-inverted and supplied to the attenuator 13. As shown in Fig. 4 (B), the output signal of the DA converter 7 is increased when the input signal a is below the reference value, and remains at the same level when it is below the reference value (in Fig. 4 (B)). , the dashed line shows the waveform of the original input signal a).

The attenuator 13 has the same structure as the attenuator 10 shown in FIG. 5 except for the amplifier 10a.

Here, in the case of reproduction below the reference value, an H level signal is supplied to the attenuator 13, so the reproduction signal level is multiplied by R2/(R1+R2) by the resistors R+ and R2 (that is, the original level On the other hand, if a reproduced signal having a value equal to or higher than the reference value is received, an L level signal is supplied to the attenuator 13, so that the reproduced signal is extracted with the same amplitude. The signal taken out from the attenuator 13 has unnecessary frequency components removed by the low-pass filter 8, and is taken out from the output terminal 9 as a signal d shown in FIG. 4(D).

As described above, the conventional devices shown in FIGS. 3(A) and 3(B) increase the amplitude of an input signal having a relatively small amplitude, then AD convert it and write it into the memory 12.
Compared to the conventional devices shown in A) and (B), it is possible to record particularly small amplitude input signals with high resolution.

However, this one requires at least one of all data bits.
bits (also used as gain bits), input signal a
The full scale special number is shown in Figure 1 (A).

The resolution was lower than that of the device shown in (B), and it had the disadvantage of causing distortion and ω noise. In this case, if the gain bits are set to 0 for several bits, the resolution at full scale will further deteriorate.

Furthermore, even when a large amplitude is present, the amplitude is considered to be small near the zero level and the amplitude is increased, so that the gain is switched throughout the waveform. For this reason, unless an attenuator 10 with extremely high gain accuracy is used, cross A'-no\-distortion occurs, resulting in a poor S/N ratio.

The present invention eliminates the above-mentioned drawbacks, and an embodiment thereof will be described with reference to FIG. 6 and subsequent figures.

FIG. 6(A) shows a block system diagram of a device for writing an audio signal into the memory of a waveform reproducing device according to the present invention.

In the same figure (A), the attenuated waveform e (Figure 7 (A)), which is the collected sound from the actual piano that enters the terminal 1, is supplied to the sample-and-hold circuit 3 via the low-pass filter 2. Here, the signal is sampled and held and supplied to the variable gain amplifier 15.

On the other hand, the digital output from the counter 6 is sent to the sample/hold circuit 3. AD converter4. The memory 16 is supplied to the variable gain amplifier 15 to operate them.

Here, the editor monitors the waveform of the signal e with a CRT or the like, and when the amplitude of the signal e becomes smaller than the reference level Vcomp and attempts to increase the amplitude and write it into the memory (time to) , perform appropriate switch operation to connect terminal 1.
A predetermined control signal is applied to 7. This control signal is supplied to the gain multiplier terminal of the variable gain amplifier 15 to increase its gain by a predetermined amount. As a result, as shown in FIG. 7(B), the variable gain amplifier 15 extracts a signal f whose amplitude has been increased by a predetermined 1 with respect to the waveform e from the point in time when one sampling time has elapsed from the time to, and the signal f is After being AD converted by the AD converter 4, it is supplied to the memory 16 and written there.

On the other hand, the control signal from the terminal 17 is supplied to a gain change code generator 18, which generates a gain change code such as ro000000 in the case of 8 bits.
0J is taken out and passed to the memory 16. This gain change code is set to a value that does not match the code corresponding to the amplitude of the signal e, that is, a positive maximum value or a negative maximum value (in this embodiment, the negative maximum value roooooooOJ as described above).

In this way, the memory 16 stores the code at the same level before the time to when the amplitude of the signal e is relatively large, and the code rooooo at the time to.

00J, and thereafter, a code of a level whose amplitude is increased by the variable gain amplifier 15 is written.

As described above, writing digital signals corresponding to the signal f into the memory 16 is performed by the manufacturer of the electronic organ, and the memory 16 in which each tone is written in this way is built into the electronic organ.

The device having the configuration shown in FIG. 6 (A>) is actually composed of a microcomputer or the like, and the signal processing is performed by a program corresponding to the microcomputer.

FIG. 6(B) shows a block system diagram of the first embodiment of the waveform reproducing device according to the present invention. When a user operates a key for a certain tone during performance, a signal corresponding to that key is read out from the memory 16 in accordance with the digital output of the counter 6, and the read signal is sent to the DA converter 7, as shown in FIG. At DA
After being converted into a signal @f, it is supplied to the variable gain amplifier 15. In this case, the signal from the memory 16 is also supplied to an AND circuit (gain change code detection circuit) 19 in which the gain change code rooooooo00J is stored in advance, where it is constantly compared with the gain change code [00000000J.

If the signal read from the memory 16 has a large amplitude portion, the output 0 of the AND circuit 19 becomes L as shown in FIG. 7(C).
Therefore, the output of the inverter 20 becomes the H level, and the switch 21a is turned on. On the other hand, since the output of the flip-flop 22 is at the L level as shown in FIG. 2(D), the gain of the variable gain amplifier 15 remains at 1. As a result, the signal of the large amplitude portion is supplied to the low-pass filter 8 at the same level, unnecessary frequency components are removed, and the signal i is outputted from the output terminal 9 as shown in FIG.

Here, if the signal read from the memory 16 has a code of 8 bits, for example, roooooooOJ, this is detected by the AND circuit 19, and the output 9 of the AND circuit 19 is 1.
The sampling time becomes TH level, and the switch 21a is turned off.
While the switch 21b is turned on, the flip-flop 2
The output g of the AND circuit 19 is at H level and is supplied to the gain down-down terminal of the variable gain amplifier 15, and the output g of the AND circuit 19 is supplied to the replacement data generation circuit 23.

By the way, the replacement data generation circuit 23 includes a DA converter 7.
The level at time 10 extracted from gain variable amplifier 1
A replacement data code whose level is decreased at step 5 and increased to the original level at time to is stored, and the replacement data code is taken out by being supplied with the output g of the AND circuit 19, and the switch 21b supplied to

As a result, in the case of an 8-bit code read from the memory 16, roooooooOJ is generated by the replacement data generation circuit 23.
After being supplied to the DA converter 7 and subjected to DA conversion, it is supplied to the variable gain amplifier 15, where the level is reduced to the level at time to.

Next, if the signal read from the memory 16 is code 8 pits, if it is after rooooooooj, then the AND circuit 1
The output g of 9 is set to L level, and the switch 21a is turned on.
Switch 21b is turned off. As a result, the signal that was written to the memory 16 with a large amplitude during editing is reduced in level by the variable gain amplifier 15 and returned to its original level, and then passed through the low-pass filter 8 as shown in FIG. The signal i shown in E) is taken out from the output terminal 9.

In addition, from the terminal 24 to the counter 6, the flip 70 knob 22
The reset signal supplied to the circuit is used to reset these to the initial state at the time of starting the circuit.

In the above embodiment, the gain change code is rooooo.

When 00J is read, it is sent to the replacement data generation circuit 2.
3 to the replacement data code, but it is limited to this.
As in the embodiment, switch 2 is used instead of the replacement data generation circuit.
5 may be provided. This one is switch 21
a, 21b and the inverter 20 are not required, and the other configurations are the same as the circuit shown in FIG. 6(B). Also, when editing, when the level of signal e reaches zero level, operate the switch and change the gain code (
For example, assume that MOOOOOOOOJ) is written in the memory 16.

In FIG. 8, when the output g of the AND circuit 19 is at L level, the movable contact piece of the switch 25 is connected to the terminal a,
The output of the variable gain amplifier 15 is supplied to the low-pass filter 8 via the LJ switch 25.

On the other hand, when the output 0 of the AND circuit 19 is at H level, the movable contact piece of the switch 25 is connected to the terminal S. As a result, the signal from the variable gain amplifier 15 (is not taken out, and the signal from the terminal 9
The signal level extracted from is zero.

FIG. 9 shows a block system diagram of a third embodiment of the apparatus of the present invention, in which the same components as in FIG. 6 and 8(B) are given the same numbers. This can be applied to the case where the amplitude of the signal e shown in FIG. 7(A) becomes small after time to and becomes large again as shown by the dashed line.

Gain change code roooo to return the gain to the original during playback by performing a switch operation at time to during editing.
oooOJ and the level code whose amplitude has been increased since then are written to the memory 16, and at time t2, the switch operation is performed again to cancel the operation of restoring the gain to the original value during playback.The gain code change code N1111111J and the amplitude after that are written. Store the restored level code in memory 1
Write to 6.

On the other hand, in the replacement data generation circuit 231 in FIG. 9, the level at time "to" taken out from the DA converter 7 is reduced in level by the variable gain amplifier 15, similar to the one shown in FIG. 6(B). While a replacement data code increased by the amount corresponding to the original level at time to is stored in the replacement data generation circuit 232, the level at time t2 taken out from the DA converter 7 is input to the variable gain amplifier 15. gain 1
A replacement data code is stored that is multiplied to the original level at time t2.

When the AND circuit 191 detects the 3-code "0OOOOOOOO", the output of the DA converter 7 is reduced in amplitude and taken out by the variable gain amplifier 15, similar to the device shown in FIG. 6(B). Ru.

When the AND circuit 192 detects the code N1111111, the signal j shown in FIG. The output is L
At the same time, the switch 21a is turned off and the switch 21b is turned on, and a replacement data code is taken out from the replacement data generation circuit 232. As a result, the code r1111111'1j is replaced with the replacement data code from the replacement data generation circuit 232 at time t2. In this case, the gain of the variable gain amplifier 15 is 1,
The replacement data code at the original level at time t2 is extracted as is without being level-varied by the variable gain amplifier 15.

After time t2, switch 21a is on and switch 21b is on.
is turned off, and the signal taken out from the memory 16 is DA-converted and then taken out at the same amplitude without being level-varied by the variable gain amplifier 15, resulting in the overall signal shown in FIG. 7(E). i and taken out from the output terminal 9.

The device shown in Figure 9 is capable of recording and reproducing, with good resolution, a signal in which the amplitude becomes small and the motion is repeated like that of a person again.
Strictly speaking, there is a time lag even if a large number of people hit the ball at the same time), it is possible to individually reproduce it with good resolution.

In the apparatus shown in FIG. 9, if the zero level of the signal C is used as a gain change code, only one replacement data generation circuit is required.

FIG. 10 shows a block system diagram of the main parts of the fourth embodiment of the device of the present invention. As shown in Fig. 7 (G), this thing is like a piano or the like between R and I! This can be applied to a waveform k that attenuates with time.

When editing 1. In the part where the amplitude of the signal is relatively small, it is multiplied by M3 at time t3 and multiplied by M4 at time t4.

At time t5, the respective gains are switched to M5 times, thereby increasing the amplitude and writing it into the memory 16, while
Time t3. t4. Gain change code r10000 at t5
000J is written to memory 16.

In FIG. 10, the gain change code read from the memory 16 is detected by the AND circuit 27.

A counter 28 counts the number of times of detection.

The output of the counter 28 is supplied to a decoder 29, where it is made into a decoded signal according to the number of times, that is, the time, and supplied to an attenuator 30, a detailed circuit diagram of which is shown in FIG. 11, and its switch 303.30a.

... are combined and turned off according to the respective decode signals.

On the other hand, due to the detection of the gain change code, switch 21b
is on, switch 21a is off, and other Jl
In lJ&'l, the switches 21a and 21b are reversed. As a result, time t3. At t4° and t5, the zero level code is taken out, and the signal from time 13 to t4 is 1/M3° at the attenuator 30, and the signal from time 14 to t5 is 1/Ma.
, the signal after time t5 is extracted as 1/M5.

In the description of the apparatus shown in FIG. 10, the gain is varied in three stages for a relatively small amplitude portion, but the gain is not limited to this, and four or more stages may be used depending on the resolution.

Further, in this embodiment, the DA converter 7 and the variable gain amplifier 15
Although these are independent configurations, a multiplication type DA converter whose output can be varied by control voltage (current) may be used, and the circuit can be easily configured in this way.

As described above, the waveform reproducing device according to the present invention stores an input signal whose level changes over time in a memory in which a level code increased by a predetermined level from a predetermined tense and a gain change code at a predetermined time are written in time series. and a gain change code detection circuit that detects the gain change code read out from the memory, and a level at which the signal whose level has been increased by a predetermined level by the output of the gain change code detection circuit is returned to its original level by decreasing the level by the predetermined level increase. Since it is configured with a variable means, it is possible to reproduce the waveform of a small amplitude input signal with a good SM ratio without causing distortion or quantization noise, and there is no gain bit in the data bits as in conventional devices. All data bits can be used as level bits, and this allows for sufficient resolution, especially for full-scale signals, compared to conventional devices, without causing distortion or quantization noise, and without causing distortion or quantization noise, unlike conventional devices. Since there is no gain switching near the zero level of the signal, there is no lossover distortion unlike in conventional equipment, and the accuracy of gain switching does not need to be so high.Furthermore, the output of the gain change code detection circuit Since a replacement data output means is provided which replaces the gain change code with a level code corresponding to the level of the input signal waveform at the above-mentioned predetermined time of the input signal waveform,
Furthermore, it is possible to obtain a waveform that is faithful to the input signal waveform, and in particular, by configuring the replacement data output means with means for replacing the level code of the input signal waveform with a zero level at a predetermined time, the signal read from the memory can be obtained. Since a switch can be used to change over whether or not to take out the signal, the circuit can be easily configured.Furthermore, the input signal whose level changes over time can be input to the first predetermined time with a level code increased by a predetermined level from the first predetermined time. A first gain change code that changes at the time, a level code that remains at the original level from a second predetermined time, and a second gain change code at the second predetermined time are written in chronological order. memory and the first
and a second gain change code, respectively, and a signal whose level has been increased by a predetermined level by the output of the first gain change code detection circuit is decreased by a predetermined level increase. The input signal whose amplitude becomes small and becomes large again can be controlled by the level variable means which returns the amplitude to the original level and stops the level reduction operation using the output of the second gain change code detection circuit. Furthermore, the level of the gradually attenuated (or increased) input signal is read out from a plurality of predetermined times, and the level of the increased signal is decreased by the level increase to restore the original level. By returning the signal to the same level, it has the advantage that, for example, a signal waveform such as a piano whose level gradually attenuates can be reproduced with good resolution.

[Brief explanation of drawings]

FIGS. 1(A) and (B) are block diagrams of an example of a conventional device, and FIGS. 2(A) and (B) are large amplitude signals. A diagram for explaining the resolution when a small amplitude signal is received; FIGS. 3(A) and 3(B) are block diagrams of other examples of conventional devices;
4(A) to 4(D) are signal waveform diagrams for explaining the operation of the conventional device, FIG. 5 is a specific circuit diagram of the attenuator in FIG. 3(A), and FIG. 6(A) is a diagram of the attenuator of the present invention device. A block system diagram of a device for writing signals into a memory, (B) is the first diagram of the device of the present invention.
7(A) to (G) are signal waveform diagrams for explaining the operation of the device of the present invention. FIG. 8 is a block diagram of the main parts of the second embodiment of the device of the present invention. 9 is a block diagram of the third embodiment of the device of the present invention, FIG. 10 is a block diagram of the main parts of the fourth embodiment of the device of the present invention, and FIG. 11 is a specific circuit diagram of the attenuator in FIG. 10. It is. 1...Input terminal, 3...Sample/hold circuit,
4...△D converter, 6... Counter, 7... DA
Converter, 9... Output terminal, 15... Variable gain amplifier, 16... Memory, 17... Control signal input terminal,
18...gain change code generator, 19.19+,
, 192.27...AND circuit, 21a, 21b, 2
5,303-305...Switch, 22...Flip 70 knob, 23.23+, 232...Replacement data generation circuit, 28...J counter, 29...Decoder, 30...Attenuator . Figure 8 Figure 9 Figure 10 Figure 11 '2n Procedural Amendment January 6, 1980 1, Case Description 1988 Patent Application No. 15366. ．． 9 No. 2,
Name of the invention: Waveform reproducing device 3, Patent of the person making the amendment Applicant address: Kumo 221 3-12 Moriya-cho, Kanayō-ku, Yokohama, Kanagawa Prefecture Name (432) Representative: President and CEO of Victor Japan Co., Ltd. Shinji Department 4, Agent Person 6: Claims and Detailed Description of the Invention in the section to be amended. 7. Contents of the amendment (1) The statement in the scope of claims in the specification is amended as shown in the attached sheet. ■ "Retrieval" written on page 13, line 4 of the same document is amended as follows. "One sampling time is taken out and replaced with the original level code" ■ "So" and "code" written in line 12 of page 13 of the same document
``Replaced with the original level code'' is added between. (4) "Level" written in line 7, page 16 of the same, "level"
and correct it. 6) Same, page 23, line 2, page 24, lines 11 and 13
Corrected ``Okeru'' in the line name to ``Okeru'' was replaced with the level code. Claims [(1) A waveform reproducing device that reads out a signal waveform that has been sampled at predetermined intervals, digitally encodes its amplitude value, and is written in a memory, converts it into an analog signal, and retrieves the signal waveform, the level of which changes over time. "Replace a changing input signal with a level code increased by a predetermined level from a predetermined time and the level code at the predetermined time." a gain change code detection circuit that detects the gain change code read from the gain change code; and a signal whose level has been increased by the predetermined level by the output of the gain change code detection circuit is decreased by the predetermined level increase and returned to the original level. A waveform reproducing device characterized by comprising a level variable means. ■ A waveform that reads out a signal waveform that has been sampled at a predetermined interval, whose amplitude value has been digitally encoded and written in a memory, and which is converted into an analog signal and extracted. In a reproducing device, an input signal whose level changes with time is written in time series with a level code in which the level is increased by a predetermined level from a predetermined time, and a gain change code at the predetermined time. a gain change code detection circuit that detects the gain change code read from the memory; and a signal whose level has been increased by the predetermined level by the output of the gain change code detection circuit, and whose level is decreased by the predetermined level increase. and output of the gain change code detecting circuit to replace the gain change code with a level code corresponding to the level of the input signal waveform at the predetermined time. A waveform reproducing device comprising: means. 2. The waveform reproducing device according to claim 2, wherein the replacement data output means is means for replacing the input signal waveform with a level code having a predetermined value at the predetermined time. (4) The waveform reproducing apparatus according to claim 2, wherein the replacement data output means is means for replacing the input signal waveform with a zero level level code at the predetermined time. ■ In a waveform reproducing device that reads out a signal waveform that has been sampled at predetermined intervals, digitally encodes its amplitude value, and writes it into a memory, converts it into an analog signal, and extracts it, the input signal whose level changes over time is a level code increased by a predetermined level from a predetermined time, a first gain change code replaced by the level code ζ at the first predetermined time, and a level code that remains at the original level from a second predetermined time. and a second gain change code that is replaced with the level code that remains unchanged at the second predetermined time; and a second one gain change code, respectively.
and a second gain change code detection circuit, and a signal whose level has been increased by the predetermined level by the output of the first gain change code detection circuit is decreased by the predetermined level increase to return it to the original level, and the signal is returned to the original level by the predetermined level increase. 1. A waveform reproducing device comprising: level variable means for stopping the level reduction operation based on the output of the gain change code detection circuit No. 2. (6) The replacement data output means is means for replacing the input signal waveform with level codes having respective predetermined values at the first and second predetermined times. The waveform reproducing device described in . (2) The replacement data output means is configured to output the first data of the input signal waveform.
6. The waveform reproducing apparatus according to claim 5, further comprising means for replacing the level code with a zero level level code at a second predetermined time. ■ In a waveform reproducing device that reads out a signal waveform that has been sampled at a predetermined interval, its amplitude value digitally coded, and written in memory, and converted to an analog signal, the level gradually attenuates (or increases) over time. a memory in which level codes obtained by increasing the input signal by a predetermined level from a plurality of predetermined times and a plurality of gain change codes replaced with the level codes at the plurality of predetermined times are written in a chronological order; a gain change code detection circuit that detects the plurality of read gain change codes; and a signal whose level has been increased by the predetermined level by the output of the gain change code detection circuit is reduced by the predetermined level increase to the original level. A waveform reproducing device comprising a level variable means for returning. (9) The gain change code detection circuit is a counter that counts the number of playbacks of the gain change code, and the level variable means is an attenuator that attenuates the level according to the number of counts by the counter. The waveform reproducing device according to scope 8. ”

Claims (1)

[Claims] (1) A waveform reproducing device that reads out a signal waveform sampled at predetermined intervals, digitally encodes its amplitude value, and writes it into a memory, converts it into an analog signal, and extracts it, A memory in which a level code in which an input signal that changes with the input signal is increased by a predetermined level from a predetermined time and a gain change code at the predetermined time is written in chronological order, and the gain change code read from the memory are detected. It is characterized by comprising a gain change code detection circuit and a level variable means that reduces the level of the signal whose level has been increased by the predetermined level increase by the predetermined level increase by the output of the gain change code detection circuit and returns it to the original level. Waveform playback device. (2) An input whose level changes over time in a waveform reproducing device that reads out a signal waveform that has been sampled at predetermined intervals, its amplitude value digitally coded, and written in memory, converted to an analog signal, and extracted. A memory in which a level code in which a signal is increased by a predetermined level from a predetermined time and a gain change code at the predetermined time are written in chronological order, and a gain change code detection unit that detects the gain change code sequentially output from the memory. circuit, a level variable means for reducing the level of the signal whose predetermined level has been increased by the output of the gain change code detection circuit by the predetermined level increase and returning it to the original level; A waveform reproducing device comprising replacement data output means for replacing and extracting a gain change code with a level code corresponding to the level of the input signal waveform at the predetermined time. 2. The waveform reproducing apparatus according to claim 2, wherein the replacement data output means is means for replacing the input signal waveform with a level code having a predetermined value at the predetermined time. (4) The waveform reproducing apparatus according to claim 2, wherein the replacement data output means is means for replacing the input signal waveform with a zero level level code at the predetermined time. (5) A waveform reproducing device that reads out a signal waveform that has been sampled at a predetermined interval, whose amplitude value is digitally coded, and written into a memory, converts it into an analog signal, and retrieves the input signal whose level changes over time. First predetermined time J:
A level code increased by a predetermined level, a first gain change code at the first predetermined time, a level code that remains at the original level from a second predetermined time, and a second gain at the second predetermined time. a memory in which change codes are written in chronological order; first and second gain change code detection circuits that respectively detect the first and second gain change codes read from the memory; The signal whose level has been increased by the predetermined level by the output of the first gain change code detection circuit is decreased by the predetermined level increase and returned to the original level, and the level is decreased by the output of the second gain change code detection circuit. A waveform reproducing device comprising: level variable means for stopping operation. e) The replacement data output means is means for replacing the input signal waveform with level codes having respective predetermined values at the first and second predetermined times. The waveform reproducing device described. The replacement data output means is configured to output the first data of the input signal waveform.
6. The waveform reproducing apparatus according to claim 5, further comprising means for replacing the level code with a zero level level code at a second predetermined time. ■ In a waveform reproducing device that reads out a signal waveform that has been sampled at a predetermined interval, its amplitude value digitally coded, and written in memory, and converted to an analog signal, the level gradually attenuates (or increases) over time. a memory in which level codes obtained by increasing input signals by a predetermined level from a plurality of predetermined times and a plurality of gain change codes at the plurality of predetermined times are written in chronological order; and a plurality of gains read from the memory. It comprises a gain change code detection circuit that detects a change code, and a level variable means that reduces the level of the signal whose level has been increased by the predetermined level increase by the predetermined level increase by the output of the gain change code detection circuit and returns it to the original level. A waveform reproducing device characterized by: (9) A patent claim characterized in that the gain change code detection path is a counter that counts the number of times the gain change code is played, and the level variable means is an attenuator that attenuates the level according to the number of counts by the counter. The waveform reproducing device according to item 8.